This invention relates to the generation of sounds into the womb of an expectant mother. More specifically, this invention provides a means to present voices or music to a fetus in a manner that the sounds more accurately resemble the same sounds as the baby will hear after birth.
It has been shown that a fetus hears sounds as early as the fifth month of pregnancy. The present invention is useable as an experimental tool to direct sounds to a fetus so that such sounds are more accurately presented to the fetus in its environment as such sounds would normally be heard after birth. Thus, the experience a fetus has in hearing sounds, including the father's and mother's voices, may aid in early language development and bonding between parents and the child. Such experimental tools can be provided to expectant mothers and none to other expectant mothers, and psychologists and developmental specialists will be able to study the effects of such sounds on the children on both groups of such mothers.
Studies have been conducted on both the ability of the fetus to hear noises as well as the ability of sounds to reach the fetus from outside the mother's body. One such recent study was discussed in "Perception auditive et reactivite foetale aux stimulations sonores," by D. Querleu et al., J. Gyn. Obst. Biol. Repr., 1981, Vol. 10, pp. 307-314 ("Auditory Perception and Reaction to Sonor Stimulation"). The authors of this article investigated the level of sound within the uterus, both internal background noise as well as external noise passing through the body. The article indicates that the global intensity of background noise within the uterus is about 65 decibels. Furthermore, it was found that sound is increasingly attenuated as the frequency increases, at the rate of six to twelve decibels per octave, and that for sounds above 2000 hertz a dangerously loud sound would be required to overcome background levels within the body. Finally, for a sound source of 110 decibels, the attenuation of the signal at 1,000 hertz is about 20 decibels.